ExxonMobil Oil Joliet Refinery
Will County, Illinois · EIA plant ID 50627 · Operator: ExxonMobil Oil Corp
Nameplate43MWSummer 37 MW
Generators3in service
Net generation187GWh12 mo to Aug 2026
Capacity factor58%gas/coal/oil units, summer MW
Heat rate8,322Btu/kWhfossil units, electric fuel, HHV
First online1986Runs as baseload
The 12-month figures include preliminary EIA-923 months, which EIA revises. Final data runs through Dec 2025.
Monthly net generation
EIA-923, all units at the plant. Net of station use; storage can go negative.
FinalPreliminary
Capacity factor by year
Net MWh ÷ (summer MW × hours), gas/coal/oil units. Each year uses that year's EIA-860 ratings; the hollow dot is the latest 12 months.
Heat rate by year
Electric fuel MMBtu × 1000 ÷ net MWh (Btu/kWh, HHV), fossil units only; CT + CA counted as one combined-cycle block.
Annual data table
| Year | Net GWh | Capacity factor | Heat rate (Btu/kWh) |
|---|---|---|---|
| 2001 | 250.4 | — | — |
| 2002 | 256.4 | — | — |
| 2003 | 203.6 | 58.7% | 9,164 |
| 2004 | 176.9 | 50.7% | 8,235 |
| 2005 | 151 | 43.4% | 8,459 |
| 2006 | 112.1 | 32.2% | 8,469 |
| 2007 | 107.6 | 30.9% | 8,101 |
| 2008 | 49.6 | 12.4% | 6,399 |
| 2009 | 110.3 | 21.9% | 7,015 |
| 2010 | 138.2 | 28.2% | 7,247 |
| 2011 | 194.1 | 45.2% | 6,539 |
| 2012 | 155.6 | 34.8% | 6,404 |
| 2013 | 188.9 | 54.3% | 7,976 |
| 2014 | 182.7 | 52.5% | 7,398 |
| 2015 | 171.7 | 49.4% | 6,423 |
| 2016 | 198.5 | 61.9% | 8,611 |
| 2017 | 194.8 | 60.9% | 8,592 |
| 2018 | 171.7 | 53.7% | 8,618 |
| 2019 | 181.7 | 56.8% | 8,577 |
| 2020 | 210.8 | 65.7% | 8,601 |
| 2021 | 186.2 | 58.2% | 8,603 |
| 2022 | 147.3 | 46.1% | 8,738 |
| 2023 | 180 | 56.3% | 8,454 |
| 2024 | 177 | 55.2% | 8,443 |
| 2025 | 185.3 | 57.9% | 8,322 |
Generators
EIA-860 (annual) with EIA-860M updates through Sep 2026. EIA-923 reports generation by plant, prime mover and fuel, not by unit, so unit-level output isn't shown.
| Gen ID | Technology | Prime mover | Nameplate MW | Summer MW | Online | Status | Planned retirement | OEM / model |
|---|---|---|---|---|---|---|---|---|
| GTG1 | Other Gases | GT | 25.7 | 22 | Nov 1987 | Operating | — | coming soon |
| MG | Other Gases | ST | 11.2 | 11.2 | May 1986 | Operating | — | coming soon |
| STG1 | Other Gases | ST | 6.5 | 3.3 | Nov 1987 | Operating (Out of service) | — | coming soon |
Owner / operator
Operator: ExxonMobil Oil Corp. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
| ExxonMobil Oil Corp | 100.0% | 43 MW |
Nearby plants
Within 80 km.
| Elwood Energy LLC | 576 MW | 5.6 km |
| MPH Elwood | 384 MW | 5.6 km |
| Jackson Generation, LLC | 1,289 MW | 6.5 km |
| Dresden Generating Station | 2,019 MW | 7.8 km |
| Dresden Island Hydroelectric Project | — | 8.4 km |
| GE-Hitachi Solar - Morris, IL | 1 MW | 8.4 km |